@samitouri / QOS-React-1 / commits / a5fc797db1

[Fizz] Replay Postponed Paths (#27379)

This forks Task into ReplayTask and RenderTask. A RenderTask is the normal mode and it has a segment to write into. A ReplayTask doesn't have a segment to write into because that has already been written but instead it has a ReplayState which keeps track of the next set of paths to follow. Once we hit a "Resume" node we convert it into a RenderTask and continue rendering from there. We can resume at either an Element position or a Slot position. An Element pointing to a component doesn't mean we resume that component, it means we resume in the child position directly below that component. Slots are slots inside arrays. Instead of statically forking most paths, I kept using the same path and checked for the existence of a segment or replay state dynamically at runtime. However, there's still quite a bit of forking here like retryRenderTask and retryReplayTask. Even in the new forks there's a lot of duplication like resumeSuspenseBoundary, replaySuspenseBoundary and renderSuspenseBoundary. There's opportunity to simplify this a bit.

Sebastian Markbåge committed Sep 15, 2023 at 15:24 UTC a5fc797db14c6e05d4d5c4dbb22a0dd70d41f5d5

4 files changed +1211 -219

packages/react-dom/src/__tests__/ReactDOMFizzServer-test.js

+1 -1

@@ -6365,6 +6365,6 @@ describe('ReactDOMFizzServer', () => {

6365 resumed.pipe(writable);

6366 });

6367

6368 - // TODO: expect(getVisibleChildren(container)).toEqual(<div>Hello</div>);

6368 + expect(getVisibleChildren(container)).toEqual(<div>Hello</div>);

6369 });

6370 });

packages/react-dom/src/__tests__/ReactDOMFizzStaticBrowser-test.js

+133 -4

@@ -105,7 +105,7 @@ describe('ReactDOMFizzStaticBrowser', () => {

105 }

106 const temp = document.createElement('div');

107 temp.innerHTML = result;

108 - insertNodesAndExecuteScripts(temp, container, null);

108 + await insertNodesAndExecuteScripts(temp, container, null);

109 }

110

111 // @gate experimental

@@ -490,7 +490,51 @@ describe('ReactDOMFizzStaticBrowser', () => {

490

491 await readIntoContainer(resumed);

492

493 - // TODO: expect(getVisibleChildren(container)).toEqual(<div>Hello</div>);

493 + expect(getVisibleChildren(container)).toEqual(

494 + <div>{['Hello', 'World']}</div>,

495 + );

496 + });

497 +

498 + // @gate enablePostpone

499 + it('supports postponing in prerender and resuming with a prefix', async () => {

500 + let prerendering = true;

501 + function Postpone() {

502 + if (prerendering) {

503 + React.unstable_postpone();

504 + }

505 + return 'World';

506 + }

507 +

508 + function App() {

509 + return (

510 + <div>

511 + <Suspense fallback="Loading...">

512 + Hello

513 + <Postpone />

514 + </Suspense>

515 + </div>

516 + );

517 + }

518 +

519 + const prerendered = await ReactDOMFizzStatic.prerender(<App />);

520 + expect(prerendered.postponed).not.toBe(null);

521 +

522 + prerendering = false;

523 +

524 + const resumed = await ReactDOMFizzServer.resume(

525 + <App />,

526 + prerendered.postponed,

527 + );

528 +

529 + await readIntoContainer(prerendered.prelude);

530 +

531 + expect(getVisibleChildren(container)).toEqual(<div>Loading...</div>);

532 +

533 + await readIntoContainer(resumed);

534 +

535 + expect(getVisibleChildren(container)).toEqual(

536 + <div>{['Hello', 'World']}</div>,

537 + );

538 });

539

540 // @gate enablePostpone

@@ -500,7 +544,51 @@ describe('ReactDOMFizzStaticBrowser', () => {

544 React.unstable_postpone();

545 });

546

547 + function App() {

548 + return (

549 + <div>

550 + <Suspense fallback="Loading...">

551 + Hi

552 + {prerendering ? Hole : 'Hello'}

553 + </Suspense>

554 + </div>

555 + );

556 + }

557 +

558 + const prerendered = await ReactDOMFizzStatic.prerender(<App />);

559 + expect(prerendered.postponed).not.toBe(null);

560 +

561 + prerendering = false;

562 +

563 + const resumed = await ReactDOMFizzServer.resume(

564 + <App />,

565 + prerendered.postponed,

566 + );

567 +

568 + await readIntoContainer(prerendered.prelude);

569 +

570 + expect(getVisibleChildren(container)).toEqual(<div>Loading...</div>);

571 +

572 + await readIntoContainer(resumed);

573 +

574 + expect(getVisibleChildren(container)).toEqual(

575 + <div>

576 + {'Hi'}

577 + {'Hello'}

578 + </div>,

579 + );

580 + });

581 +

582 + // @gate enablePostpone

583 + it('supports postponing in a nested array', async () => {

584 + let prerendering = true;

585 + const Hole = React.lazy(async () => {

586 + React.unstable_postpone();

587 + });

588 function Postpone() {

589 + if (prerendering) {

590 + React.unstable_postpone();

591 + }

592 return 'Hello';

593 }

594

@@ -509,7 +597,48 @@ describe('ReactDOMFizzStaticBrowser', () => {

597 <div>

598 <Suspense fallback="Loading...">

599 Hi

512 - {prerendering ? Hole : <Postpone />}

600 + {[<Postpone key="key" />, prerendering ? Hole : 'World']}

601 + </Suspense>

602 + </div>

603 + );

604 + }

605 +

606 + const prerendered = await ReactDOMFizzStatic.prerender(<App />);

607 + expect(prerendered.postponed).not.toBe(null);

608 +

609 + prerendering = false;

610 +

611 + const resumed = await ReactDOMFizzServer.resume(

612 + <App />,

613 + prerendered.postponed,

614 + );

615 +

616 + await readIntoContainer(prerendered.prelude);

617 +

618 + expect(getVisibleChildren(container)).toEqual(<div>Loading...</div>);

619 +

620 + await readIntoContainer(resumed);

621 +

622 + expect(getVisibleChildren(container)).toEqual(

623 + <div>{['Hi', 'Hello', 'World']}</div>,

624 + );

625 + });

626 +

627 + // @gate enablePostpone

628 + it('supports postponing in lazy as a direct child', async () => {

629 + let prerendering = true;

630 + const Hole = React.lazy(async () => {

631 + React.unstable_postpone();

632 + });

633 + function Postpone() {

634 + return prerendering ? Hole : 'Hello';

635 + }

636 +

637 + function App() {

638 + return (

639 + <div>

640 + <Suspense fallback="Loading...">

641 + <Postpone key="key" />

642 </Suspense>

643 </div>

644 );

@@ -531,7 +660,7 @@ describe('ReactDOMFizzStaticBrowser', () => {

660

661 await readIntoContainer(resumed);

662

534 - // TODO: expect(getVisibleChildren(container)).toEqual(<div>Hello</div>);

663 + expect(getVisibleChildren(container)).toEqual(<div>Hello</div>);

664 });

665

666 // @gate enablePostpone

packages/react-server/src/ReactFizzServer.js

+1072 -213

@@ -168,7 +168,8 @@ export type KeyNode = [

168 const REPLAY_NODE = 0;

169 const REPLAY_SUSPENSE_BOUNDARY = 1;

170 const RESUME_ELEMENT = 2;

171 -const RESUME_SLOT = 3;

171 +const RESUME_SUSPENSE_BOUNDARY = 3;

172 +const RESUME_SLOT = 4;

173

174 type ReplaySuspenseBoundary = [

175 1, // REPLAY_SUSPENSE_BOUNDARY

@@ -188,6 +189,14 @@ type ReplayNode =

189 ]

190 | ReplaySuspenseBoundary;

191

192 +type ResumeSuspenseBoundary = [

193 + 3, // RESUME_SUSPENSE_BOUNDARY

194 + string | null /* name */,

195 + string | number /* key */,

196 + SuspenseBoundaryID /* id */,

197 + number /* rootSegmentID */,

198 +];

199 +

200 type ResumeElement = [

201 2, // RESUME_ELEMENT

202 string | null /* name */,

@@ -196,12 +205,16 @@ type ResumeElement = [

205 ];

206

207 type ResumeSlot = [

199 - 3, // RESUME_SLOT

208 + 4, // RESUME_SLOT

209 number /* index */,

210 number /* segment id */,

211 ];

212

204 -type ResumableNode = ReplayNode | ResumeElement | ResumeSlot;

213 +type ResumableNode =

214 + | ReplayNode

215 + | ResumeElement

216 + | ResumeSuspenseBoundary

217 + | ResumeSlot;

218

219 type PostponedHoles = {

220 workingMap: Map<KeyNode, ReplayNode>,

@@ -230,7 +243,8 @@ type SuspenseBoundary = {

243 keyPath: Root | KeyNode,

244 };

245

233 -export type Task = {

246 +type RenderTask = {

247 + replay: null,

248 node: ReactNodeList,

249 childIndex: number,

250 ping: () => void,

@@ -246,6 +260,32 @@ export type Task = {

260 thenableState: null | ThenableState,

261 };

262

263 +type ReplaySet = {

264 + nodes: Array<ResumableNode>, // the possible paths to follow down the replaying

265 + pendingTasks: number, // tracks the number of tasks currently tracking this set of nodes

266 + // if pending tasks reach zero but there are still nodes left, it means we couldn't find

267 + // them all in the tree, so we need to abort and client render the boundary.

268 +};

269 +

270 +type ReplayTask = {

271 + replay: ReplaySet,

272 + node: ReactNodeList,

273 + childIndex: number,

274 + ping: () => void,

275 + blockedBoundary: Root | SuspenseBoundary,

276 + blockedSegment: null, // we don't write to anything when we replay

277 + abortSet: Set<Task>, // the abortable set that this task belongs to

278 + keyPath: Root | KeyNode, // the path of all parent keys currently rendering

279 + formatContext: FormatContext, // the format's specific context (e.g. HTML/SVG/MathML)

280 + legacyContext: LegacyContext, // the current legacy context that this task is executing in

281 + context: ContextSnapshot, // the current new context that this task is executing in

282 + treeContext: TreeContext, // the current tree context that this task is executing in

283 + componentStack: null | ComponentStackNode, // DEV-only component stack

284 + thenableState: null | ThenableState,

285 +};

286 +

287 +export type Task = RenderTask | ReplayTask;

288 +

289 const PENDING = 0;

290 const COMPLETED = 1;

291 const FLUSHED = 2;

@@ -400,7 +440,7 @@ export function createRequest(

440 );

441 // There is no parent so conceptually, we're unblocked to flush this segment.

442 rootSegment.parentFlushed = true;

403 - const rootTask = createTask(

443 + const rootTask = createRenderTask(

444 request,

445 null,

446 children,

@@ -490,25 +530,13 @@ export function resumeRequest(

530 onFatalError: onFatalError === undefined ? noop : onFatalError,

531 formState: null,

532 };

493 - // This segment represents the root fallback.

494 - const rootSegment = createPendingSegment(

495 - request,

496 - 0,

497 - null,

498 - postponedState.rootFormatContext,

499 - // Root segments are never embedded in Text on either edge

500 - false,

501 - false,

502 - );

503 - // There is no parent so conceptually, we're unblocked to flush this segment.

504 - rootSegment.parentFlushed = true;

505 - const rootTask = createTask(

533 + const rootTask = createReplayTask(

534 request,

535 null,

536 + {nodes: postponedState.resumablePath, pendingTasks: 0},

537 children,

538 -1,

539 null,

511 - rootSegment,

540 abortSet,

541 null,

542 postponedState.rootFormatContext,

@@ -560,7 +588,7 @@ function createSuspenseBoundary(

588 };

589 }

590

563 -function createTask(

591 +function createRenderTask(

592 request: Request,

593 thenableState: ThenableState | null,

594 node: ReactNodeList,

@@ -573,14 +601,15 @@ function createTask(

601 legacyContext: LegacyContext,

602 context: ContextSnapshot,

603 treeContext: TreeContext,

576 -): Task {

604 +): RenderTask {

605 request.allPendingTasks++;

606 if (blockedBoundary === null) {

607 request.pendingRootTasks++;

608 } else {

609 blockedBoundary.pendingTasks++;

610 }

583 - const task: Task = ({

611 + const task: RenderTask = ({

612 + replay: null,

613 node,

614 childIndex,

615 ping: () => pingTask(request, task),

@@ -601,6 +630,49 @@ function createTask(

630 return task;

631 }

632

633 +function createReplayTask(

634 + request: Request,

635 + thenableState: ThenableState | null,

636 + replay: ReplaySet,

637 + node: ReactNodeList,

638 + childIndex: number,

639 + blockedBoundary: Root | SuspenseBoundary,

640 + abortSet: Set<Task>,

641 + keyPath: Root | KeyNode,

642 + formatContext: FormatContext,

643 + legacyContext: LegacyContext,

644 + context: ContextSnapshot,

645 + treeContext: TreeContext,

646 +): ReplayTask {

647 + request.allPendingTasks++;

648 + if (blockedBoundary === null) {

649 + request.pendingRootTasks++;

650 + } else {

651 + blockedBoundary.pendingTasks++;

652 + }

653 + replay.pendingTasks++;

654 + const task: ReplayTask = ({

655 + replay,

656 + node,

657 + childIndex,

658 + ping: () => pingTask(request, task),

659 + blockedBoundary,

660 + blockedSegment: null,

661 + abortSet,

662 + keyPath,

663 + formatContext,

664 + legacyContext,

665 + context,

666 + treeContext,

667 + thenableState,

668 + }: any);

669 + if (__DEV__) {

670 + task.componentStack = null;

671 + }

672 + abortSet.add(task);

673 + return task;

674 +}

675 +

676 function createPendingSegment(

677 request: Request,

678 index: number,

@@ -739,10 +811,19 @@ function fatalError(request: Request, error: mixed): void {

811

812 function renderSuspenseBoundary(

813 request: Request,

742 - task: Task,

814 + someTask: Task,

815 keyPath: Root | KeyNode,

816 props: Object,

817 ): void {

818 + if (someTask.replay !== null) {

819 + throw new Error(

820 + 'Did not expect to see a Suspense boundary in this slot. ' +

821 + "The tree doesn't match so React will fallback to client rendering.",

822 + );

823 + }

824 + // $FlowFixMe: Refined.

825 + const task: RenderTask = someTask;

826 +

827 pushBuiltInComponentStackInDEV(task, 'Suspense');

828

829 const prevKeyPath = task.keyPath;

@@ -866,7 +947,7 @@ function renderSuspenseBoundary(

947

948 // We create suspended task for the fallback because we don't want to actually work

949 // on it yet in case we finish the main content, so we queue for later.

869 - const suspendedFallbackTask = createTask(

950 + const suspendedFallbackTask = createRenderTask(

951 request,

952 null,

953 fallback,

@@ -891,6 +972,203 @@ function renderSuspenseBoundary(

972 popComponentStackInDEV(task);

973 }

974

975 +function replaySuspenseBoundary(

976 + request: Request,

977 + task: ReplayTask,

978 + props: Object,

979 + replayNode: ReplaySuspenseBoundary,

980 +): void {

981 + pushBuiltInComponentStackInDEV(task, 'Suspense');

982 +

983 + const previousReplaySet: ReplaySet = task.replay;

984 +

985 + const parentBoundary = task.blockedBoundary;

986 +

987 + const content: ReactNodeList = props.children;

988 +

989 + const fallbackAbortSet: Set<Task> = new Set();

990 + const resumedBoundary = createSuspenseBoundary(

991 + request,

992 + fallbackAbortSet,

993 + task.keyPath,

994 + );

995 + resumedBoundary.parentFlushed = true;

996 + // We restore the same id of this boundary as was used during prerender.

997 + resumedBoundary.id = replayNode[4];

998 + resumedBoundary.rootSegmentID = replayNode[5];

999 +

1000 + // We can reuse the current context and task to render the content immediately without

1001 + // context switching. We just need to temporarily switch which boundary and replay node

1002 + // we're writing to. If something suspends, it'll spawn new suspended task with that context.

1003 + task.blockedBoundary = resumedBoundary;

1004 + task.replay = {nodes: replayNode[3], pendingTasks: 1};

1005 + if (enableFloat) {

1006 + // Does this even matter for replaying?

1007 + setCurrentlyRenderingBoundaryResourcesTarget(

1008 + request.renderState,

1009 + resumedBoundary.resources,

1010 + );

1011 + }

1012 + try {

1013 + // We use the safe form because we don't handle suspending here. Only error handling.

1014 + renderNode(request, task, content, -1);

1015 + if (

1016 + resumedBoundary.pendingTasks === 0 &&

1017 + resumedBoundary.status === PENDING

1018 + ) {

1019 + resumedBoundary.status = COMPLETED;

1020 + request.completedBoundaries.push(resumedBoundary);

1021 + }

1022 + if (task.replay.pendingTasks === 1 && task.replay.nodes.length > 0) {

1023 + throw new Error(

1024 + "Couldn't find all resumable slots by key/index during replaying. " +

1025 + "The tree doesn't match so React will fallback to client rendering.",

1026 + );

1027 + }

1028 + task.replay.pendingTasks--;

1029 + } catch (error) {

1030 + resumedBoundary.status = CLIENT_RENDERED;

1031 + let errorDigest;

1032 + if (

1033 + enablePostpone &&

1034 + typeof error === 'object' &&

1035 + error !== null &&

1036 + error.$$typeof === REACT_POSTPONE_TYPE

1037 + ) {

1038 + const postponeInstance: Postpone = (error: any);

1039 + logPostpone(request, postponeInstance.message);

1040 + // TODO: Figure out a better signal than a magic digest value.

1041 + errorDigest = 'POSTPONE';

1042 + } else {

1043 + errorDigest = logRecoverableError(request, error);

1044 + }

1045 + resumedBoundary.errorDigest = errorDigest;

1046 + if (__DEV__) {

1047 + captureBoundaryErrorDetailsDev(resumedBoundary, error);

1048 + }

1049 +

1050 + task.replay.pendingTasks--;

1051 +

1052 + // We don't need to decrement any task numbers because we didn't spawn any new task.

1053 + // We don't need to schedule any task because we know the parent has written yet.

1054 + // We do need to fallthrough to create the fallback though.

1055 + } finally {

1056 + if (enableFloat) {

1057 + setCurrentlyRenderingBoundaryResourcesTarget(

1058 + request.renderState,

1059 + parentBoundary ? parentBoundary.resources : null,

1060 + );

1061 + }

1062 + task.blockedBoundary = parentBoundary;

1063 + task.replay = previousReplaySet;

1064 + }

1065 + // TODO: Should this be in the finally?

1066 + popComponentStackInDEV(task);

1067 +}

1068 +

1069 +function resumeSuspenseBoundary(

1070 + request: Request,

1071 + task: ReplayTask,

1072 + props: Object,

1073 + replayNode: ResumeSuspenseBoundary,

1074 +): void {

1075 + pushBuiltInComponentStackInDEV(task, 'Suspense');

1076 +

1077 + const previousReplaySet: ReplaySet = task.replay;

1078 +

1079 + const parentBoundary = task.blockedBoundary;

1080 +

1081 + const content: ReactNodeList = props.children;

1082 +

1083 + const fallbackAbortSet: Set<Task> = new Set();

1084 + const resumedBoundary = createSuspenseBoundary(

1085 + request,

1086 + fallbackAbortSet,

1087 + task.keyPath,

1088 + );

1089 + resumedBoundary.parentFlushed = true;

1090 + // We restore the same id of this boundary as was used during prerender.

1091 + resumedBoundary.id = replayNode[3];

1092 + resumedBoundary.rootSegmentID = replayNode[4];

1093 +

1094 + const resumedSegment = createPendingSegment(

1095 + request,

1096 + 0,

1097 + null,

1098 + task.formatContext,

1099 + false,

1100 + false,

1101 + );

1102 + resumedSegment.parentFlushed = true;

1103 + resumedSegment.id = replayNode[4];

1104 +

1105 + // We can reuse the current context and task to render the content immediately without

1106 + // context switching. We just need to temporarily switch which boundary and replay node

1107 + // we're writing to. If something suspends, it'll spawn new suspended task with that context.

1108 + task.blockedBoundary = resumedBoundary;

1109 + if (enableFloat) {

1110 + // Does this even matter for replaying?

1111 + setCurrentlyRenderingBoundaryResourcesTarget(

1112 + request.renderState,

1113 + resumedBoundary.resources,

1114 + );

1115 + }

1116 + try {

1117 + // Convert the current ReplayTask to a RenderTask.

1118 + const renderTask: RenderTask = (task: any);

1119 + renderTask.replay = null;

1120 + renderTask.blockedSegment = resumedSegment;

1121 + // We use the safe form because we don't handle suspending here. Only error handling.

1122 + renderNode(request, task, content, -1);

1123 + resumedSegment.status = COMPLETED;

1124 + queueCompletedSegment(resumedBoundary, resumedSegment);

1125 + if (

1126 + resumedBoundary.pendingTasks === 0 &&

1127 + resumedBoundary.status === PENDING

1128 + ) {

1129 + resumedBoundary.status = COMPLETED;

1130 + request.completedBoundaries.push(resumedBoundary);

1131 + }

1132 + } catch (error) {

1133 + resumedBoundary.status = CLIENT_RENDERED;

1134 + let errorDigest;

1135 + if (

1136 + enablePostpone &&

1137 + typeof error === 'object' &&

1138 + error !== null &&

1139 + error.$$typeof === REACT_POSTPONE_TYPE

1140 + ) {

1141 + const postponeInstance: Postpone = (error: any);

1142 + logPostpone(request, postponeInstance.message);

1143 + // TODO: Figure out a better signal than a magic digest value.

1144 + errorDigest = 'POSTPONE';

1145 + } else {

1146 + errorDigest = logRecoverableError(request, error);

1147 + }

1148 + resumedBoundary.errorDigest = errorDigest;

1149 + if (__DEV__) {

1150 + captureBoundaryErrorDetailsDev(resumedBoundary, error);

1151 + }

1152 +

1153 + // We don't need to decrement any task numbers because we didn't spawn any new task.

1154 + // We don't need to schedule any task because we know the parent has written yet.

1155 + // We do need to fallthrough to create the fallback though.

1156 + } finally {

1157 + if (enableFloat) {

1158 + setCurrentlyRenderingBoundaryResourcesTarget(

1159 + request.renderState,

1160 + parentBoundary ? parentBoundary.resources : null,

1161 + );

1162 + }

1163 + task.blockedBoundary = parentBoundary;

1164 + // Restore to a ReplayTask

1165 + task.blockedSegment = null;

1166 + task.replay = previousReplaySet;

1167 + }

1168 + // TODO: Should this be in the finally?

1169 + popComponentStackInDEV(task);

1170 +}

1171 +

1172 function renderBackupSuspenseBoundary(

1173 request: Request,

1174 task: Task,

@@ -901,13 +1179,18 @@ function renderBackupSuspenseBoundary(

1179

1180 const content = props.children;

1181 const segment = task.blockedSegment;

904 -

905 - pushStartCompletedSuspenseBoundary(segment.chunks);

1182 const prevKeyPath = task.keyPath;

1183 task.keyPath = keyPath;

908 - renderNode(request, task, content, -1);

1184 + if (segment === null) {

1185 + // Replay

1186 + renderNode(request, task, content, -1);

1187 + } else {

1188 + // Render

1189 + pushStartCompletedSuspenseBoundary(segment.chunks);

1190 + renderNode(request, task, content, -1);

1191 + pushEndCompletedSuspenseBoundary(segment.chunks);

1192 + }

1193 task.keyPath = prevKeyPath;

910 - pushEndCompletedSuspenseBoundary(segment.chunks);

1194

1195 popComponentStackInDEV(task);

1196 }

@@ -921,38 +1204,56 @@ function renderHostElement(

1204 ): void {

1205 pushBuiltInComponentStackInDEV(task, type);

1206 const segment = task.blockedSegment;

1207 + if (segment === null) {

1208 + // Replay

1209 + const children = props.children; // TODO: Make this a Config for replaying.

1210 + const prevContext = task.formatContext;

1211 + const prevKeyPath = task.keyPath;

1212 + task.formatContext = getChildFormatContext(prevContext, type, props);

1213 + task.keyPath = keyPath;

1214

925 - const children = pushStartInstance(

926 - segment.chunks,

927 - type,

928 - props,

929 - request.resumableState,

930 - request.renderState,

931 - task.formatContext,

932 - segment.lastPushedText,

933 - );

934 - segment.lastPushedText = false;

935 - const prevContext = task.formatContext;

936 - const prevKeyPath = task.keyPath;

937 - task.formatContext = getChildFormatContext(prevContext, type, props);

938 - task.keyPath = keyPath;

1215 + // We use the non-destructive form because if something suspends, we still

1216 + // need to pop back up and finish this subtree of HTML.

1217 + renderNode(request, task, children, -1);

1218 +

1219 + // We expect that errors will fatal the whole task and that we don't need

1220 + // the correct context. Therefore this is not in a finally.

1221 + task.formatContext = prevContext;

1222 + task.keyPath = prevKeyPath;

1223 + } else {

1224 + // Render

1225 + const children = pushStartInstance(

1226 + segment.chunks,

1227 + type,

1228 + props,

1229 + request.resumableState,

1230 + request.renderState,

1231 + task.formatContext,

1232 + segment.lastPushedText,

1233 + );

1234 + segment.lastPushedText = false;

1235 + const prevContext = task.formatContext;

1236 + const prevKeyPath = task.keyPath;

1237 + task.formatContext = getChildFormatContext(prevContext, type, props);

1238 + task.keyPath = keyPath;

1239

940 - // We use the non-destructive form because if something suspends, we still

941 - // need to pop back up and finish this subtree of HTML.

942 - renderNode(request, task, children, -1);

1240 + // We use the non-destructive form because if something suspends, we still

1241 + // need to pop back up and finish this subtree of HTML.

1242 + renderNode(request, task, children, -1);

1243

944 - // We expect that errors will fatal the whole task and that we don't need

945 - // the correct context. Therefore this is not in a finally.

946 - task.formatContext = prevContext;

947 - task.keyPath = prevKeyPath;

948 - pushEndInstance(

949 - segment.chunks,

950 - type,

951 - props,

952 - request.resumableState,

953 - prevContext,

954 - );

955 - segment.lastPushedText = false;

1244 + // We expect that errors will fatal the whole task and that we don't need

1245 + // the correct context. Therefore this is not in a finally.

1246 + task.formatContext = prevContext;

1247 + task.keyPath = prevKeyPath;

1248 + pushEndInstance(

1249 + segment.chunks,

1250 + type,

1251 + props,

1252 + request.resumableState,

1253 + prevContext,

1254 + );

1255 + segment.lastPushedText = false;

1256 + }

1257 popComponentStackInDEV(task);

1258 }

1259

@@ -1645,9 +1946,234 @@ function renderElement(

1946 );

1947 }

1948

1648 -// $FlowFixMe[missing-local-annot]

1649 -function validateIterable(iterable, iteratorFn: Function): void {

1650 - if (__DEV__) {

1949 +function resumeNode(

1950 + request: Request,

1951 + task: ReplayTask,

1952 + segmentId: number,

1953 + node: ReactNodeList,

1954 + childIndex: number,

1955 +): void {

1956 + const prevReplay = task.replay;

1957 + const blockedBoundary = task.blockedBoundary;

1958 + const resumedSegment = createPendingSegment(

1959 + request,

1960 + 0,

1961 + null,

1962 + task.formatContext,

1963 + false,

1964 + false,

1965 + );

1966 + resumedSegment.id = segmentId;

1967 + resumedSegment.parentFlushed = true;

1968 + try {

1969 + // Convert the current ReplayTask to a RenderTask.

1970 + const renderTask: RenderTask = (task: any);

1971 + renderTask.replay = null;

1972 + renderTask.blockedSegment = resumedSegment;

1973 + renderNode(request, task, node, childIndex);

1974 + resumedSegment.status = COMPLETED;

1975 + if (blockedBoundary === null) {

1976 + request.completedRootSegment = resumedSegment;

1977 + } else {

1978 + queueCompletedSegment(blockedBoundary, resumedSegment);

1979 + if (blockedBoundary.parentFlushed) {

1980 + request.partialBoundaries.push(blockedBoundary);

1981 + }

1982 + }

1983 + } finally {

1984 + // Restore to a ReplayTask.

1985 + task.replay = prevReplay;

1986 + task.blockedSegment = null;

1987 + }

1988 +}

1989 +

1990 +function resumeElement(

1991 + request: Request,

1992 + task: ReplayTask,

1993 + keyPath: Root | KeyNode,

1994 + segmentId: number,

1995 + prevThenableState: ThenableState | null,

1996 + type: any,

1997 + props: Object,

1998 + ref: any,

1999 +): void {

2000 + const prevReplay = task.replay;

2001 + const blockedBoundary = task.blockedBoundary;

2002 + const resumedSegment = createPendingSegment(

2003 + request,

2004 + 0,

2005 + null,

2006 + task.formatContext,

2007 + false,

2008 + false,

2009 + );

2010 + resumedSegment.id = segmentId;

2011 + resumedSegment.parentFlushed = true;

2012 + try {

2013 + // Convert the current ReplayTask to a RenderTask.

2014 + const renderTask: RenderTask = (task: any);

2015 + renderTask.replay = null;

2016 + renderTask.blockedSegment = resumedSegment;

2017 + renderElement(request, task, keyPath, prevThenableState, type, props, ref);

2018 + resumedSegment.status = COMPLETED;

2019 + if (blockedBoundary === null) {

2020 + request.completedRootSegment = resumedSegment;

2021 + } else {

2022 + queueCompletedSegment(blockedBoundary, resumedSegment);

2023 + if (blockedBoundary.parentFlushed) {

2024 + request.partialBoundaries.push(blockedBoundary);

2025 + }

2026 + }

2027 + } finally {

2028 + // Restore to a ReplayTask.

2029 + task.replay = prevReplay;

2030 + task.blockedSegment = null;

2031 + }

2032 +}

2033 +

2034 +function replayElement(

2035 + request: Request,

2036 + task: ReplayTask,

2037 + keyPath: Root | KeyNode,

2038 + prevThenableState: ThenableState | null,

2039 + name: null | string,

2040 + keyOrIndex: number | string,

2041 + childIndex: number,

2042 + type: any,

2043 + props: Object,

2044 + ref: any,

2045 + replay: ReplaySet,

2046 +): void {

2047 + // We're replaying. Find the path to follow.

2048 + const replayNodes = replay.nodes;

2049 + for (let i = 0; i < replayNodes.length; i++) {

2050 + // Flow doesn't support refinement on tuples so we do it manually here.

2051 + const candidate: any = replayNodes[i];

2052 + switch (candidate[0]) {

2053 + case REPLAY_NODE: {

2054 + const node: ReplayNode = candidate;

2055 + if (keyOrIndex === node[2]) {

2056 + // Let's double check that the component name matches as a precaution.

2057 + if (name !== null && name !== node[1]) {

2058 + throw new Error(

2059 + 'Expected to see a component of type "' +

2060 + name +

2061 + '" in this slot. ' +

2062 + "The tree doesn't match so React will fallback to client rendering.",

2063 + );

2064 + }

2065 + // Matched a replayable path.

2066 + task.replay = {nodes: node[3], pendingTasks: 1};

2067 + try {

2068 + renderElement(

2069 + request,

2070 + task,

2071 + keyPath,

2072 + prevThenableState,

2073 + type,

2074 + props,

2075 + ref,

2076 + );

2077 + // We finished rendering this node, so now we can consume this

2078 + // slot. This must happen after in case we rerender this task.

2079 + replayNodes.splice(i, 1);

2080 + } finally {

2081 + task.replay.pendingTasks--;

2082 + if (

2083 + task.replay.pendingTasks === 0 &&

2084 + task.replay.nodes.length > 0

2085 + ) {

2086 + throw new Error(

2087 + "Couldn't find all resumable slots by key/index during replaying. " +

2088 + "The tree doesn't match so React will fallback to client rendering.",

2089 + );

2090 + }

2091 + task.replay = replay;

2092 + }

2093 + }

2094 + continue;

2095 + }

2096 + case REPLAY_SUSPENSE_BOUNDARY: {

2097 + const node: ReplaySuspenseBoundary = candidate;

2098 + if (keyOrIndex === node[2]) {

2099 + // Let's double check that the component type matches.

2100 + if (type !== REACT_SUSPENSE_TYPE) {

2101 + throw new Error(

2102 + 'Expected to see a Suspense boundary in this slot. ' +

2103 + "The tree doesn't match so React will fallback to client rendering.",

2104 + );

2105 + }

2106 + // Matched a replayable path.

2107 + replaySuspenseBoundary(request, task, props, node);

2108 + // We finished rendering this node, so now we can consume this

2109 + // slot. This must happen after in case we rerender this task.

2110 + replayNodes.splice(i, 1);

2111 + }

2112 + continue;

2113 + }

2114 + case RESUME_ELEMENT: {

2115 + const node: ResumeElement = candidate;

2116 + if (keyOrIndex === node[2]) {

2117 + // Let's double check that the component name matches as a precaution.

2118 + if (name !== node[1]) {

2119 + throw new Error(

2120 + 'Expected to see a component of type "' +

2121 + (name || 'unknown') +

2122 + '" in this slot. ' +

2123 + "The tree doesn't match so React will fallback to client rendering.",

2124 + );

2125 + }

2126 + // Matched a resumable element.

2127 +

2128 + const segmentId = node[3];

2129 +

2130 + resumeElement(

2131 + request,

2132 + task,

2133 + keyPath,

2134 + segmentId,

2135 + prevThenableState,

2136 + type,

2137 + props,

2138 + ref,

2139 + );

2140 +

2141 + // We finished rendering this node, so now we can consume this

2142 + // slot. This must happen after in case we rerender this task.

2143 + replayNodes.splice(i, 1);

2144 + }

2145 + continue;

2146 + }

2147 + case RESUME_SUSPENSE_BOUNDARY: {

2148 + const node: ResumeSuspenseBoundary = candidate;

2149 + if (keyOrIndex === node[2]) {

2150 + // Let's double check that the component name matches as a precaution.

2151 + if (type !== REACT_SUSPENSE_TYPE) {

2152 + throw new Error(

2153 + 'Expected to see a Suspense boundary in this slot. ' +

2154 + "The tree doesn't match so React will fallback to client rendering.",

2155 + );

2156 + }

2157 + // Matched a resumable suspense boundary.

2158 + resumeSuspenseBoundary(request, task, props, node);

2159 +

2160 + // We finished rendering this node, so now we can consume this

2161 + // slot. This must happen after in case we rerender this task.

2162 + replayNodes.splice(i, 1);

2163 + }

2164 + continue;

2165 + }

2166 + // For RESUME_SLOT we ignore them here and assume we've handled them

2167 + // separately already.

2168 + }

2169 + }

2170 + // We didn't find any matching nodes. We assume that this element was already

2171 + // rendered in the prelude and skip it.

2172 +}

2173 +

2174 +// $FlowFixMe[missing-local-annot]

2175 +function validateIterable(iterable, iteratorFn: Function): void {

2176 + if (__DEV__) {

2177 // We don't support rendering Generators because it's a mutation.

2178 // See https://github.com/facebook/react/issues/12995

2179 if (

@@ -1748,20 +2274,37 @@ function renderNodeDestructiveImpl(

2274 const props = element.props;

2275 const ref = element.ref;

2276 const name = getComponentNameFromType(type);

1751 - const keyPath = [

1752 - task.keyPath,

1753 - name,

1754 - key == null ? (childIndex === -1 ? 0 : childIndex) : key,

1755 - ];

1756 - renderElement(

1757 - request,

1758 - task,

1759 - keyPath,

1760 - prevThenableState,

1761 - type,

1762 - props,

1763 - ref,

1764 - );

2277 + const keyOrIndex =

2278 + key == null ? (childIndex === -1 ? 0 : childIndex) : key;

2279 + const keyPath = [task.keyPath, name, keyOrIndex];

2280 + if (task.replay !== null) {

2281 + replayElement(

2282 + request,

2283 + task,

2284 + keyPath,

2285 + prevThenableState,

2286 + name,

2287 + keyOrIndex,

2288 + childIndex,

2289 + type,

2290 + props,

2291 + ref,

2292 + task.replay,

2293 + );

2294 + // No matches found for this node. We assume it's already emitted in the

2295 + // prelude and skip it during the replay.

2296 + } else {

2297 + // We're doing a plain render.

2298 + renderElement(

2299 + request,

2300 + task,

2301 + keyPath,

2302 + prevThenableState,

2303 + type,

2304 + props,

2305 + ref,

2306 + );

2307 + }

2308 return;

2309 }

2310 case REACT_PORTAL_TYPE:

@@ -1882,23 +2425,33 @@ function renderNodeDestructiveImpl(

2425

2426 if (typeof node === 'string') {

2427 const segment = task.blockedSegment;

1885 - segment.lastPushedText = pushTextInstance(

1886 - task.blockedSegment.chunks,

1887 - node,

1888 - request.renderState,

1889 - segment.lastPushedText,

1890 - );

2428 + if (segment === null) {

2429 + // We assume a text node doesn't have a representation in the replay set,

2430 + // since it can't postpone. If it does, it'll be left unmatched and error.

2431 + } else {

2432 + segment.lastPushedText = pushTextInstance(

2433 + segment.chunks,

2434 + node,

2435 + request.renderState,

2436 + segment.lastPushedText,

2437 + );

2438 + }

2439 return;

2440 }

2441

2442 if (typeof node === 'number') {

2443 const segment = task.blockedSegment;

1896 - segment.lastPushedText = pushTextInstance(

1897 - task.blockedSegment.chunks,

1898 - '' + node,

1899 - request.renderState,

1900 - segment.lastPushedText,

1901 - );

2444 + if (segment === null) {

2445 + // We assume a text node doesn't have a representation in the replay set,

2446 + // since it can't postpone. If it does, it'll be left unmatched and error.

2447 + } else {

2448 + segment.lastPushedText = pushTextInstance(

2449 + segment.chunks,

2450 + '' + node,

2451 + request.renderState,

2452 + segment.lastPushedText,

2453 + );

2454 + }

2455 return;

2456 }

2457

@@ -1918,13 +2471,85 @@ function renderChildrenArray(

2471 task: Task,

2472 children: Array<any>,

2473 childIndex: number,

1921 -) {

2474 +): void {

2475 const prevKeyPath = task.keyPath;

2476 if (childIndex !== -1) {

1924 - task.keyPath = [task.keyPath, '', childIndex];

2477 + task.keyPath = [task.keyPath, 'Fragment', childIndex];

2478 + if (task.replay !== null) {

2479 + // If we're supposed follow this array, we'd expect to see a ReplayNode matching

2480 + // this fragment.

2481 + const replayTask: ReplayTask = task;

2482 + const replay = task.replay;

2483 + const replayNodes = replay.nodes;

2484 + for (let j = 0; j < replayNodes.length; j++) {

2485 + const replayNode = replayNodes[j];

2486 + if (replayNode[0] !== REPLAY_NODE) {

2487 + continue;

2488 + }

2489 + const node: ReplayNode = (replayNode: any);

2490 + if (node[2] !== childIndex) {

2491 + continue;

2492 + }

2493 + // Matched a replayable path.

2494 + replayTask.replay = {nodes: node[3], pendingTasks: 1};

2495 + try {

2496 + renderChildrenArray(request, task, children, -1);

2497 + } finally {

2498 + replayTask.replay.pendingTasks--;

2499 + if (

2500 + replayTask.replay.pendingTasks === 0 &&

2501 + replayTask.replay.nodes.length > 0

2502 + ) {

2503 + throw new Error(

2504 + "Couldn't find all resumable slots by key/index during replaying. " +

2505 + "The tree doesn't match so React will fallback to client rendering.",

2506 + );

2507 + }

2508 + replayTask.replay = replay;

2509 + }

2510 + // We finished rendering this node, so now we can consume this

2511 + // slot. This must happen after in case we rerender this task.

2512 + replayNodes.splice(j, 1);

2513 + break;

2514 + }

2515 + task.keyPath = prevKeyPath;

2516 + return;

2517 + }

2518 }

2519 const prevTreeContext = task.treeContext;

2520 const totalChildren = children.length;

2521 +

2522 + if (task.replay !== null) {

2523 + // Replay

2524 + // First we need to check if we have any resume slots at this level.

2525 + // TODO: This could be simpler if we just stored RESUME_SLOT in a separate set.

2526 + let hadOtherReplayNodes = false;

2527 + const replayNodes = task.replay.nodes;

2528 + for (let j = 0; j < replayNodes.length; ) {

2529 + const replayNode = replayNodes[j];

2530 + if (replayNode[0] !== RESUME_SLOT) {

2531 + hadOtherReplayNodes = true;

2532 + j++; // skip

2533 + continue;

2534 + }

2535 + const resumeSlot: ResumeSlot = (replayNode: any);

2536 + const i = resumeSlot[1]; // The index of the child to resume.

2537 + const segmentId = resumeSlot[2];

2538 + task.treeContext = pushTreeContext(prevTreeContext, totalChildren, i);

2539 + resumeNode(request, task, segmentId, children[i], i);

2540 + // We finished rendering this node, so now we can consume this

2541 + // slot. This must happen after in case we rerender this task.

2542 + replayNodes.splice(j, 1);

2543 + }

2544 + // If had non-resume slot nodes, we need to also try to match them below.

2545 + if (!hadOtherReplayNodes) {

2546 + // If we didn't, we can bail early.

2547 + task.treeContext = prevTreeContext;

2548 + task.keyPath = prevKeyPath;

2549 + return;

2550 + }

2551 + }

2552 +

2553 for (let i = 0; i < totalChildren; i++) {

2554 const node = children[i];

2555 task.treeContext = pushTreeContext(prevTreeContext, totalChildren, i);

@@ -1932,6 +2557,7 @@ function renderChildrenArray(

2557 // up and render the sibling if something suspends.

2558 renderNode(request, task, node, i);

2559 }

2560 +

2561 // Because this context is always set right before rendering every child, we

2562 // only need to reset it to the previous value at the very end.

2563 task.treeContext = prevTreeContext;

@@ -1945,8 +2571,13 @@ function trackPostpone(

2571 segment: Segment,

2572 ): void {

2573 segment.status = POSTPONED;

1948 - // We know that this will leave a hole so we might as well assign an ID now.

1949 - segment.id = request.nextSegmentId++;

2574 +

2575 + const keyPath = task.keyPath;

2576 + if (keyPath === null) {

2577 + throw new Error(

2578 + 'It should not be possible to postpone at the root. This is a bug in React.',

2579 + );

2580 + }

2581

2582 const boundary = task.blockedBoundary;

2583 if (boundary !== null && boundary.status === PENDING) {

@@ -1965,29 +2596,52 @@ function trackPostpone(

2596 'It should not be possible to postpone at the root. This is a bug in React.',

2597 );

2598 }

1968 - const children: Array<ResumableNode> = [];

1969 - const boundaryNode: ReplaySuspenseBoundary = [

1970 - REPLAY_SUSPENSE_BOUNDARY,

1971 - boundaryKeyPath[1],

1972 - boundaryKeyPath[2],

1973 - children,

1974 - boundary.id,

1975 - boundary.rootSegmentID,

1976 - ];

1977 - trackedPostpones.workingMap.set(boundaryKeyPath, boundaryNode);

1978 - addToReplayParent(boundaryNode, boundaryKeyPath[0], trackedPostpones);

2599 +

2600 + if (boundaryKeyPath === keyPath && task.childIndex === -1) {

2601 + // Since we postponed directly in the Suspense boundary we can't have written anything

2602 + // to its segment. Therefore this will end up becoming the root segment.

2603 + segment.id = boundary.rootSegmentID;

2604 + // We postponed directly inside the Suspense boundary so we mark this for resuming.

2605 + const boundaryNode: ResumeSuspenseBoundary = [

2606 + RESUME_SUSPENSE_BOUNDARY,

2607 + boundaryKeyPath[1],

2608 + boundaryKeyPath[2],

2609 + boundary.id,

2610 + boundary.rootSegmentID,

2611 + ];

2612 + addToReplayParent(boundaryNode, boundaryKeyPath[0], trackedPostpones);

2613 + return;

2614 + } else {

2615 + const children: Array<ResumableNode> = [];

2616 + const boundaryNode: ReplaySuspenseBoundary = [

2617 + REPLAY_SUSPENSE_BOUNDARY,

2618 + boundaryKeyPath[1],

2619 + boundaryKeyPath[2],

2620 + children,

2621 + boundary.id,

2622 + boundary.rootSegmentID,

2623 + ];

2624 + trackedPostpones.workingMap.set(boundaryKeyPath, boundaryNode);

2625 + addToReplayParent(boundaryNode, boundaryKeyPath[0], trackedPostpones);

2626 + // Fall through to add the child node.

2627 + }

2628 }

2629

1981 - const keyPath = task.keyPath;

1982 - if (keyPath === null) {

1983 - throw new Error(

1984 - 'It should not be possible to postpone at the root. This is a bug in React.',

1985 - );

2630 + // We know that this will leave a hole so we might as well assign an ID now.

2631 + // We might have one already if we had a parent that gave us its ID.

2632 + if (segment.id === -1) {

2633 + if (segment.parentFlushed && boundary !== null) {

2634 + // If this segment's parent was already flushed, it means we really just

2635 + // skipped the parent and this segment is now the root.

2636 + segment.id = boundary.rootSegmentID;

2637 + } else {

2638 + segment.id = request.nextSegmentId++;

2639 + }

2640 }

2641

2642 if (task.childIndex === -1) {

1989 - // Resume at the position before the first array

1990 - const resumableElement = [

2643 + // Resume starting from directly inside the previous parent element.

2644 + const resumableElement: ResumeElement = [

2645 RESUME_ELEMENT,

2646 keyPath[1],

2647 keyPath[2],

@@ -2003,7 +2657,7 @@ function trackPostpone(

2657

2658 function injectPostponedHole(

2659 request: Request,

2006 - task: Task,

2660 + task: RenderTask,

2661 reason: string,

2662 ): Segment {

2663 logPostpone(request, reason);

@@ -2026,9 +2680,41 @@ function injectPostponedHole(

2680 return newSegment;

2681 }

2682

2029 -function spawnNewSuspendedTask(

2683 +function spawnNewSuspendedReplayTask(

2684 request: Request,

2031 - task: Task,

2685 + task: ReplayTask,

2686 + thenableState: ThenableState | null,

2687 + x: Wakeable,

2688 +): void {

2689 + const newTask = createReplayTask(

2690 + request,

2691 + thenableState,

2692 + task.replay,

2693 + task.node,

2694 + task.childIndex,

2695 + task.blockedBoundary,

2696 + task.abortSet,

2697 + task.keyPath,

2698 + task.formatContext,

2699 + task.legacyContext,

2700 + task.context,

2701 + task.treeContext,

2702 + );

2703 +

2704 + if (__DEV__) {

2705 + if (task.componentStack !== null) {

2706 + // We pop one task off the stack because the node that suspended will be tried again,

2707 + // which will add it back onto the stack.

2708 + newTask.componentStack = task.componentStack.parent;

2709 + }

2710 + }

2711 + const ping = newTask.ping;

2712 + x.then(ping, ping);

2713 +}

2714 +

2715 +function spawnNewSuspendedRenderTask(

2716 + request: Request,

2717 + task: RenderTask,

2718 thenableState: ThenableState | null,

2719 x: Wakeable,

2720 ): void {

@@ -2048,7 +2734,7 @@ function spawnNewSuspendedTask(

2734 segment.children.push(newSegment);

2735 // Reset lastPushedText for current Segment since the new Segment "consumed" it

2736 segment.lastPushedText = false;

2051 - const newTask = createTask(

2737 + const newTask = createRenderTask(

2738 request,

2739 thenableState,

2740 task.node,

@@ -2082,12 +2768,6 @@ function renderNode(

2768 node: ReactNodeList,

2769 childIndex: number,

2770 ): void {

2085 - // Store how much we've pushed at this point so we can reset it in case something

2086 - // suspended partially through writing something.

2087 - const segment = task.blockedSegment;

2088 - const childrenLength = segment.children.length;

2089 - const chunkLength = segment.chunks.length;

2090 -

2771 // Snapshot the current context in case something throws to interrupt the

2772 // process.

2773 const previousFormatContext = task.formatContext;

@@ -2099,102 +2779,164 @@ function renderNode(

2779 if (__DEV__) {

2780 previousComponentStack = task.componentStack;

2781 }

2102 - try {

2103 - return renderNodeDestructive(request, task, null, node, childIndex);

2104 - } catch (thrownValue) {

2105 - resetHooksState();

2782 + let x;

2783 + // Store how much we've pushed at this point so we can reset it in case something

2784 + // suspended partially through writing something.

2785 + const segment = task.blockedSegment;

2786 + if (segment === null) {

2787 + // Replay

2788 + try {

2789 + return renderNodeDestructive(request, task, null, node, childIndex);

2790 + } catch (thrownValue) {

2791 + resetHooksState();

2792 +

2793 + x =

2794 + thrownValue === SuspenseException

2795 + ? // This is a special type of exception used for Suspense. For historical

2796 + // reasons, the rest of the Suspense implementation expects the thrown

2797 + // value to be a thenable, because before `use` existed that was the

2798 + // (unstable) API for suspending. This implementation detail can change

2799 + // later, once we deprecate the old API in favor of `use`.

2800 + getSuspendedThenable()

2801 + : thrownValue;

2802 +

2803 + if (typeof x === 'object' && x !== null) {

2804 + // $FlowFixMe[method-unbinding]

2805 + if (typeof x.then === 'function') {

2806 + const wakeable: Wakeable = (x: any);

2807 + const thenableState = getThenableStateAfterSuspending();

2808 + spawnNewSuspendedReplayTask(

2809 + request,

2810 + // $FlowFixMe: Refined.

2811 + task,

2812 + thenableState,

2813 + wakeable,

2814 + );

2815

2107 - // Reset the write pointers to where we started.

2108 - segment.children.length = childrenLength;

2109 - segment.chunks.length = chunkLength;

2816 + // Restore the context. We assume that this will be restored by the inner

2817 + // functions in case nothing throws so we don't use "finally" here.

2818 + task.formatContext = previousFormatContext;

2819 + task.legacyContext = previousLegacyContext;

2820 + task.context = previousContext;

2821 + task.keyPath = previousKeyPath;

2822 + task.treeContext = previousTreeContext;

2823 + // Restore all active ReactContexts to what they were before.

2824 + switchContext(previousContext);

2825 + if (__DEV__) {

2826 + task.componentStack = previousComponentStack;

2827 + }

2828 + return;

2829 + }

2830 + }

2831

2111 - const x =

2112 - thrownValue === SuspenseException

2113 - ? // This is a special type of exception used for Suspense. For historical

2114 - // reasons, the rest of the Suspense implementation expects the thrown

2115 - // value to be a thenable, because before `use` existed that was the

2116 - // (unstable) API for suspending. This implementation detail can change

2117 - // later, once we deprecate the old API in favor of `use`.

2118 - getSuspendedThenable()

2119 - : thrownValue;

2832 + // TODO: Abort any undiscovered Suspense boundaries in the ResumableNode.

2833 + }

2834 + } else {

2835 + // Render

2836 + const childrenLength = segment.children.length;

2837 + const chunkLength = segment.chunks.length;

2838 + try {

2839 + return renderNodeDestructive(request, task, null, node, childIndex);

2840 + } catch (thrownValue) {

2841 + resetHooksState();

2842 +

2843 + // Reset the write pointers to where we started.

2844 + segment.children.length = childrenLength;

2845 + segment.chunks.length = chunkLength;

2846 +

2847 + x =

2848 + thrownValue === SuspenseException

2849 + ? // This is a special type of exception used for Suspense. For historical

2850 + // reasons, the rest of the Suspense implementation expects the thrown

2851 + // value to be a thenable, because before `use` existed that was the

2852 + // (unstable) API for suspending. This implementation detail can change

2853 + // later, once we deprecate the old API in favor of `use`.

2854 + getSuspendedThenable()

2855 + : thrownValue;

2856 +

2857 + if (typeof x === 'object' && x !== null) {

2858 + // $FlowFixMe[method-unbinding]

2859 + if (typeof x.then === 'function') {

2860 + const wakeable: Wakeable = (x: any);

2861 + const thenableState = getThenableStateAfterSuspending();

2862 + spawnNewSuspendedRenderTask(

2863 + request,

2864 + // $FlowFixMe: Refined.

2865 + task,

2866 + thenableState,

2867 + wakeable,

2868 + );

2869

2121 - if (typeof x === 'object' && x !== null) {

2122 - // $FlowFixMe[method-unbinding]

2123 - if (typeof x.then === 'function') {

2124 - const wakeable: Wakeable = (x: any);

2125 - const thenableState = getThenableStateAfterSuspending();

2126 - spawnNewSuspendedTask(request, task, thenableState, wakeable);

2127 -

2128 - // Restore the context. We assume that this will be restored by the inner

2129 - // functions in case nothing throws so we don't use "finally" here.

2130 - task.formatContext = previousFormatContext;

2131 - task.legacyContext = previousLegacyContext;

2132 - task.context = previousContext;

2133 - task.keyPath = previousKeyPath;

2134 - task.treeContext = previousTreeContext;

2135 - // Restore all active ReactContexts to what they were before.

2136 - switchContext(previousContext);

2137 - if (__DEV__) {

2138 - task.componentStack = previousComponentStack;

2870 + // Restore the context. We assume that this will be restored by the inner

2871 + // functions in case nothing throws so we don't use "finally" here.

2872 + task.formatContext = previousFormatContext;

2873 + task.legacyContext = previousLegacyContext;

2874 + task.context = previousContext;

2875 + task.keyPath = previousKeyPath;

2876 + task.treeContext = previousTreeContext;

2877 + // Restore all active ReactContexts to what they were before.

2878 + switchContext(previousContext);

2879 + if (__DEV__) {

2880 + task.componentStack = previousComponentStack;

2881 + }

2882 + return;

2883 }

2140 - return;

2141 - }

2142 - if (

2143 - enablePostpone &&

2144 - request.trackedPostpones !== null &&

2145 - x.$$typeof === REACT_POSTPONE_TYPE &&

2146 - task.blockedBoundary !== null // TODO: Support holes in the shell

2147 - ) {

2148 - // If we're tracking postpones, we inject a hole here and continue rendering

2149 - // sibling. Similar to suspending. If we're not tracking, we treat it more like

2150 - // an error. Notably this doesn't spawn a new task since nothing will fill it

2151 - // in during this prerender.

2152 - const postponeInstance: Postpone = (x: any);

2153 - const trackedPostpones = request.trackedPostpones;

2154 - const postponedSegment = injectPostponedHole(

2155 - request,

2156 - task,

2157 - postponeInstance.message,

2158 - );

2159 - trackPostpone(request, trackedPostpones, task, postponedSegment);

2160 -

2161 - // Restore the context. We assume that this will be restored by the inner

2162 - // functions in case nothing throws so we don't use "finally" here.

2163 - task.formatContext = previousFormatContext;

2164 - task.legacyContext = previousLegacyContext;

2165 - task.context = previousContext;

2166 - task.keyPath = previousKeyPath;

2167 - task.treeContext = previousTreeContext;

2168 - // Restore all active ReactContexts to what they were before.

2169 - switchContext(previousContext);

2170 - if (__DEV__) {

2171 - task.componentStack = previousComponentStack;

2884 + if (

2885 + enablePostpone &&

2886 + request.trackedPostpones !== null &&

2887 + x.$$typeof === REACT_POSTPONE_TYPE &&

2888 + task.blockedBoundary !== null // TODO: Support holes in the shell

2889 + ) {

2890 + // If we're tracking postpones, we inject a hole here and continue rendering

2891 + // sibling. Similar to suspending. If we're not tracking, we treat it more like

2892 + // an error. Notably this doesn't spawn a new task since nothing will fill it

2893 + // in during this prerender.

2894 + const postponeInstance: Postpone = (x: any);

2895 + const trackedPostpones = request.trackedPostpones;

2896 + const postponedSegment = injectPostponedHole(

2897 + request,

2898 + ((task: any): RenderTask), // We don't use ReplayTasks in prerenders.

2899 + postponeInstance.message,

2900 + );

2901 + trackPostpone(request, trackedPostpones, task, postponedSegment);

2902 +

2903 + // Restore the context. We assume that this will be restored by the inner

2904 + // functions in case nothing throws so we don't use "finally" here.

2905 + task.formatContext = previousFormatContext;

2906 + task.legacyContext = previousLegacyContext;

2907 + task.context = previousContext;

2908 + task.keyPath = previousKeyPath;

2909 + task.treeContext = previousTreeContext;

2910 + // Restore all active ReactContexts to what they were before.

2911 + switchContext(previousContext);

2912 + if (__DEV__) {

2913 + task.componentStack = previousComponentStack;

2914 + }

2915 + return;

2916 }

2173 - return;

2917 }

2918 }

2176 - // Restore the context. We assume that this will be restored by the inner

2177 - // functions in case nothing throws so we don't use "finally" here.

2178 - task.formatContext = previousFormatContext;

2179 - task.legacyContext = previousLegacyContext;

2180 - task.context = previousContext;

2181 - task.keyPath = previousKeyPath;

2182 - task.treeContext = previousTreeContext;

2183 - // Restore all active ReactContexts to what they were before.

2184 - switchContext(previousContext);

2185 - if (__DEV__) {

2186 - task.componentStack = previousComponentStack;

2187 - }

2188 - // We assume that we don't need the correct context.

2189 - // Let's terminate the rest of the tree and don't render any siblings.

2190 - throw x;

2919 }

2920 + // Restore the context. We assume that this will be restored by the inner

2921 + // functions in case nothing throws so we don't use "finally" here.

2922 + task.formatContext = previousFormatContext;

2923 + task.legacyContext = previousLegacyContext;

2924 + task.context = previousContext;

2925 + task.keyPath = previousKeyPath;

2926 + task.treeContext = previousTreeContext;

2927 + // Restore all active ReactContexts to what they were before.

2928 + switchContext(previousContext);

2929 + if (__DEV__) {

2930 + task.componentStack = previousComponentStack;

2931 + }

2932 + // We assume that we don't need the correct context.

2933 + // Let's terminate the rest of the tree and don't render any siblings.

2934 + throw x;

2935 }

2936

2937 function erroredTask(

2938 request: Request,

2939 boundary: Root | SuspenseBoundary,

2197 - segment: Segment,

2940 error: mixed,

2941 ) {

2942 // Report the error to a global handler.

@@ -2213,6 +2955,9 @@ function erroredTask(

2955 errorDigest = logRecoverableError(request, error);

2956 }

2957 if (boundary === null) {

2958 + // TODO: If the shell errors during a replay, that's not a fatal error. Instead

2959 + // we should be able to recover by client rendering all the root boundaries in

2960 + // the ReplaySet and any already matched.

2961 fatalError(request, error);

2962 } else {

2963 boundary.pendingTasks--;

@@ -2249,8 +2994,17 @@ function abortTaskSoft(this: Request, task: Task): void {

2994 const request: Request = this;

2995 const boundary = task.blockedBoundary;

2996 const segment = task.blockedSegment;

2252 - segment.status = ABORTED;

2253 - finishedTask(request, boundary, segment);

2997 + if (segment !== null) {

2998 + segment.status = ABORTED;

2999 + finishedTask(request, boundary, segment);

3000 + }

3001 +}

3002 +

3003 +function abortRemainingResumableNodes(

3004 + nodes: Array<ResumableNode>,

3005 + error: mixed,

3006 +): void {

3007 + // TODO: Abort any undiscovered Suspense boundaries in the ReplaySet.

3008 }

3009

3010 function abortTask(task: Task, request: Request, error: mixed): void {

@@ -2258,7 +3012,16 @@ function abortTask(task: Task, request: Request, error: mixed): void {

3012 // client rendered mode.

3013 const boundary = task.blockedBoundary;

3014 const segment = task.blockedSegment;

2261 - segment.status = ABORTED;

3015 + if (segment === null) {

3016 + // $FlowFixMe: Refined.

3017 + const replay: ReplaySet = task.replay;

3018 + replay.pendingTasks--;

3019 + if (replay.pendingTasks === 0) {

3020 + abortRemainingResumableNodes(replay.nodes, error);

3021 + }

3022 + } else {

3023 + segment.status = ABORTED;

3024 + }

3025

3026 if (boundary === null) {

3027 request.allPendingTasks--;

@@ -2318,9 +3081,7 @@ function queueCompletedSegment(

3081 if (

3082 segment.chunks.length === 0 &&

3083 segment.children.length === 1 &&

2321 - segment.children[0].boundary === null &&

2322 - // Typically the id would not be assigned yet but if it's a postponed segment it might be.

2323 - segment.children[0].id === -1

3084 + segment.children[0].boundary === null

3085 ) {

3086 // This is an empty segment. There's nothing to write, so we can instead transfer the ID

3087 // to the child. That way any existing references point to the child.

@@ -2339,10 +3100,10 @@ function queueCompletedSegment(

3100 function finishedTask(

3101 request: Request,

3102 boundary: Root | SuspenseBoundary,

2342 - segment: Segment,

3103 + segment: null | Segment,

3104 ) {

3105 if (boundary === null) {

2345 - if (segment.parentFlushed) {

3106 + if (segment !== null && segment.parentFlushed) {

3107 if (request.completedRootSegment !== null) {

3108 throw new Error(

3109 'There can only be one root segment. This is a bug in React.',

@@ -2367,7 +3128,7 @@ function finishedTask(

3128 boundary.status = COMPLETED;

3129 }

3130 // This must have been the last segment we were waiting on. This boundary is now complete.

2370 - if (segment.parentFlushed) {

3131 + if (segment !== null && segment.parentFlushed) {

3132 // Our parent segment already flushed, so we need to schedule this segment to be emitted.

3133 // If it is a segment that was aborted, we'll write other content instead so we don't need

3134 // to emit it.

@@ -2387,7 +3148,7 @@ function finishedTask(

3148 boundary.fallbackAbortableTasks.forEach(abortTaskSoft, request);

3149 boundary.fallbackAbortableTasks.clear();

3150 } else {

2390 - if (segment.parentFlushed) {

3151 + if (segment !== null && segment.parentFlushed) {

3152 // Our parent already flushed, so we need to schedule this segment to be emitted.

3153 // If it is a segment that was aborted, we'll write other content instead so we don't need

3154 // to emit it.

@@ -2425,6 +3186,27 @@ function retryTask(request: Request, task: Task): void {

3186 );

3187 }

3188 const segment = task.blockedSegment;

3189 + if (segment === null) {

3190 + retryReplayTask(

3191 + request,

3192 + // $FlowFixMe: Refined.

3193 + task,

3194 + );

3195 + } else {

3196 + retryRenderTask(

3197 + request,

3198 + // $FlowFixMe: Refined.

3199 + task,

3200 + segment,

3201 + );

3202 + }

3203 +}

3204 +

3205 +function retryRenderTask(

3206 + request: Request,

3207 + task: RenderTask,

3208 + segment: Segment,

3209 +): void {

3210 if (segment.status !== PENDING) {

3211 // We completed this by other means before we had a chance to retry it.

3212 return;

@@ -2513,7 +3295,82 @@ function retryTask(request: Request, task: Task): void {

3295 }

3296 task.abortSet.delete(task);

3297 segment.status = ERRORED;

2516 - erroredTask(request, task.blockedBoundary, segment, x);

3298 + erroredTask(request, task.blockedBoundary, x);

3299 + return;

3300 + } finally {

3301 + if (enableFloat) {

3302 + setCurrentlyRenderingBoundaryResourcesTarget(request.renderState, null);

3303 + }

3304 + if (__DEV__) {

3305 + currentTaskInDEV = prevTaskInDEV;

3306 + }

3307 + }

3308 +}

3309 +

3310 +function retryReplayTask(request: Request, task: ReplayTask): void {

3311 + if (task.replay.pendingTasks === 0) {

3312 + // There are no pending tasks working on this set, so we must have aborted.

3313 + return;

3314 + }

3315 +

3316 + // We restore the context to what it was when we suspended.

3317 + // We don't restore it after we leave because it's likely that we'll end up

3318 + // needing a very similar context soon again.

3319 + switchContext(task.context);

3320 + let prevTaskInDEV = null;

3321 + if (__DEV__) {

3322 + prevTaskInDEV = currentTaskInDEV;

3323 + currentTaskInDEV = task;

3324 + }

3325 +

3326 + try {

3327 + // We call the destructive form that mutates this task. That way if something

3328 + // suspends again, we can reuse the same task instead of spawning a new one.

3329 +

3330 + // Reset the task's thenable state before continuing, so that if a later

3331 + // component suspends we can reuse the same task object. If the same

3332 + // component suspends again, the thenable state will be restored.

3333 + const prevThenableState = task.thenableState;

3334 + task.thenableState = null;

3335 +

3336 + renderNodeDestructive(request, task, prevThenableState, task.node, -1);

3337 +

3338 + if (task.replay.pendingTasks === 1 && task.replay.nodes.length > 0) {

3339 + throw new Error(

3340 + "Couldn't find all resumable slots by key/index during replaying. " +

3341 + "The tree doesn't match so React will fallback to client rendering.",

3342 + );

3343 + }

3344 + task.replay.pendingTasks--;

3345 +

3346 + task.abortSet.delete(task);

3347 + finishedTask(request, task.blockedBoundary, null);

3348 + } catch (thrownValue) {

3349 + resetHooksState();

3350 +

3351 + const x =

3352 + thrownValue === SuspenseException

3353 + ? // This is a special type of exception used for Suspense. For historical

3354 + // reasons, the rest of the Suspense implementation expects the thrown

3355 + // value to be a thenable, because before `use` existed that was the

3356 + // (unstable) API for suspending. This implementation detail can change

3357 + // later, once we deprecate the old API in favor of `use`.

3358 + getSuspendedThenable()

3359 + : thrownValue;

3360 +

3361 + if (typeof x === 'object' && x !== null) {

3362 + // $FlowFixMe[method-unbinding]

3363 + if (typeof x.then === 'function') {

3364 + // Something suspended again, let's pick it back up later.

3365 + const ping = task.ping;

3366 + x.then(ping, ping);

3367 + task.thenableState = getThenableStateAfterSuspending();

3368 + return;

3369 + }

3370 + }

3371 + task.replay.pendingTasks--;

3372 + task.abortSet.delete(task);

3373 + erroredTask(request, task.blockedBoundary, x);

3374 return;

3375 } finally {

3376 if (enableFloat) {

@@ -3011,7 +3868,9 @@ function flushCompletedQueues(

3868 if (

3869 !enablePostpone ||

3870 request.trackedPostpones === null ||

3014 - request.trackedPostpones.root.length === 0

3871 + // We check the working map instead of the root because the root could've

3872 + // been mutated at this point if it was passed straight through to resume().

3873 + request.trackedPostpones.workingMap.size === 0

3874 ) {

3875 writePostamble(destination, request.resumableState);

3876 }

scripts/error-codes/codes.json

+5 -1

@@ -471,5 +471,9 @@

471 "483": "Hooks are not supported inside an async component. This error is often caused by accidentally adding `'use client'` to a module that was originally written for the server.",

472 "484": "A Server Component was postponed. The reason is omitted in production builds to avoid leaking sensitive details.",

473 "485": "Cannot update form state while rendering.",

474 - "486": "It should not be possible to postpone at the root. This is a bug in React."

474 + "486": "It should not be possible to postpone at the root. This is a bug in React.",

475 + "487": "Did not expect to see a Suspense boundary in this slot. The tree doesn't match so React will fallback to client rendering.",

476 + "488": "Couldn't find all resumable slots by key/index during replaying. The tree doesn't match so React will fallback to client rendering.",

477 + "489": "Expected to see a component of type \"%s\" in this slot. The tree doesn't match so React will fallback to client rendering.",

478 + "490": "Expected to see a Suspense boundary in this slot. The tree doesn't match so React will fallback to client rendering."

479 }

\ No newline at end of file